The present invention relates to a device for use in cholangiography or similar procedures.
Cholangiography may be defined as an X-ray of the biliary duct system of a patient to determine whether gall stones are present in the system. During cholecystectomy, i.e., surgical removal of the patient's gall bladder, the surgeon usually attempts to ascertain whether gall stones are present in the duct system, particularly the common bile duct, and thus must be removed. However, choledochotomy, i.e., the surgical incision of the common bile duct, should be avoided if stones are not present in the common duct, since this procedure, just as overlooked stones, may be a source of post-cholecystectomy morbidity. Thus, cholangiography should be performed before surgical intervention into the common duct to eliminate an unnecessary choledochotomy.
In the past, operative cholangiography has been most simply performed in the following manner. A syringe containing a saline solution is attached to a proximal end of a catheter, an incision is made in the patient's cystic duct, which extends between the gall bladder and the common duct, and a distal end of the saline filled catheter is inserted through the incision and is positioned adjacent the juncture of the cystic duct and common duct. Next, the syringe plunger is depressed in order to irrigate the duct system with the saline solution, thus flushing the common duct to remove bile fluid, debris, and air, and to provide an indication that the common duct is not blocked. Normally, a relatively small quantity of saline solution is required to perform the irrigation procedure.
The irrigation syringe is then removed from the catheter, and another syringe containing a liquid contrast medium is attached to the proximal end of the catheter, after which the contrast medium is ejected from the catheter into the duct system. At this time, a cholangiogram, i.e., an X-ray, is obtained of the duct system, on which the stones appear as dark round shadows since they are less dense to the X-rays than the contrast medium. Additional cholangiograms are normally obtained while using increased quantities of the contrast medium.
Air bubbles, if present in the duct system during cholangiography, also appear as dark round shadows similar to stones on the cholangiograms. Hence, air must be prevented from entering the duct system during cholangiography, since the bubbles are likely to be interpreted as stones on the cholangiogram. In the past, the cholangiography devices offered an opportunity for air to enter the system when the syringes are changed. Thus, air bubbles may be injected into the duct system by the prior devices, and may result in an unnecessary and undesired choledochotomy attendant with loss of confidence in cholangiography by the surgeon when no stones are found during the choledochotomy.